// @(#)Queue.java   7/2003
// Copyright (c) 1998-2003, Distributed Real-time Computing Lab (DRCL) 
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package drcl.inet.core;

import drcl.comp.*;

public abstract class Queue extends drcl.comp.queue.ActiveQueue implements InetCoreConstants
{
  {
    // input port, follows PktFilter
    addPort(new Port(Port.PortType_IN), drcl.net.Module.PortGroup_UP);
    _setRequesting(true);
  }
  
  public Queue()
  { super(); }
  
  public Queue(String id_)
  { super(id_); }
  
  
  public void reset()
  {
    super.reset();
    _setRequesting(true);
  }
  
  public String info(String prefix_)
  {
    return prefix_ + drcl.util.StringUtil.finalPortionClassName(getClass()) + ", in " + mode + " mode" + "\n"
      + super.info(prefix_)
      + prefix_ + "Blocked? " + !_isRequesting() + "\n";
  }
    
  public void duplicate(Object source_)
  {
    super.duplicate(source_);
    Queue that_ = (Queue)source_;
    mode = that_.mode;
  }
  
  /** For a subclass to create the configuration port for other components to configure this component. */
  protected Port createConfigPort()
  { return addServerPort(CONFIG_PORT_ID); }

  /**
   * Sets the capacity (in bytes) of the queue.
   * @param capacity_ the new capacity.
   */
  public abstract void setCapacity(int capacity_);
  
  /** Returns the capacity of the queue. */
  public abstract int getCapacity();
  
  /** Returns the current size of the queue.  */
  public abstract int getSize();

  String mode = BYTE_MODE;
  
  /**
   * Sets the operation mode. Byte mode is the default mode.
   * @param mode_ either "packet" or "byte".
   */
  public void setMode(String mode_)
  { mode = mode_; }
  
  public String getMode()
  { return mode; }
  
  protected final boolean isByteMode()
  { return mode.equals(BYTE_MODE); }
  
  protected final boolean isPacketMode()
  { return mode.equals(PACKET_MODE); }
}
